Miami vs urban center

Miami and urban center both are nouns.

Word	Noun	Adjective	Verb	Adverb
Miami	Yes	No	No	No
urban center	Yes	No	No	No

Miami (noun)	urban center (noun)
a city and resort in southeastern Florida on Biscayne Bay; the best known city in Florida; a haven for retirees and a refuge for Cubans fleeing Castro	a large and densely populated urban area; may include several independent administrative districts
a member of the extinct Algonquian people formerly living in northern Indiana and southern Michigan